A childhood belief about under my bed

I never used to believe in monsters however i believe that all these kids that believe in monsters under the bed are telling the truth as why do they all report the same occurence a monster that will grab their feet or arms its gotta be more than coincidense also i actually saw the monster under my bed and i have an excellent ability to recall in detail events that happened to me when i was younger than 4 anyways i looked under the bed and saw a dark shape sort of furry but had brilliant white eyes and a large cheshire cat grin whith white teeth just lying under the bed grinning at me strangely i wasnt too afraid i also saw small figures standing on the windowsill behind the curtain and i can recall everything down to the placement of furniture and the colour of the walls and to this day and im 21 i still run and jump into bed and tuck the blanket under my body even though i cant rationalise it i get a real feeling of terror and of being watched every night